Chocolate Sheet Cake with Peanut Butter Icing


Chocolate Sheet Cake with Peanut Butter Icing is my Aunt Mary’s recipe. Rich and decadent – make sure you’ve got some milk on hand!

Happy Election Day!

Did you get out and vote? I did for the very first time! My Grandma, who was born in 1919, the year Amendment 19 passed giving women the right to vote, made me promise a few years ago that I would vote this election, and I did. For her, for me, and because she yelled at me for not doing it last time. Eep!

It’s just that, in my early 20s I felt like my one little vote was insignificant, and had less than zero interest in politics. I now know that every vote counts, plus I’m a little older and wiser, well, older anyways, and where the candidate I voted for stands on several key issues is incredibly important to me.

Plus, similar to the lottery where you can’t win if you don’t play, when it comes to the key issues, you can’t complain if you don’t vote!

Or something like that.

Anyways, I left the booth feeling excited and decided to bake a cake to celebrate. Or because I’ve been dying for a bite of rich and ultra-decadent Chocolate Sheet Cake with Peanut Butter Icing for months. I KNOW!

This recipe is from my Aunt Mary, whom my family and I visited on our road trip out east this summer. Mary comes from a long line of incredible Italian cooks, and has a feast ready for us every time we come. Cookies, sausages, pasta, and, this summer, Chocolate Sheet Cake with Peanut Butter Icing.

In all the years we’ve been visiting my Aunt & Uncle, she’d never made this cake, but after devouring her famous sausage and pepper rolls ’til we thought we might burst our first night there, she disappeared into the kitchen and reappeared a minute later triumphantly holding a massive pan of it for dessert.

Somehow we each found a way to fit a slice in. ;)

This ridiculously moist chocolate sheet cake slathered with a luscious peanut butter icing when it’s still warm from the oven tastes like a giant Reese’s Peanut Butter Cup. Luckily my Aunt Mary was more than happy to share the recipe with me, so I could share it with you. Whee!

Start the Chocolate Sheet Cake by bringing 1 cup butter, 1 cup water, and 1/4 cup cocoa powder to a boil in a saucepan, then set aside to cool slightly. Also set aside your urge to ladle the concoction into a mug and drink it. Trust me – this only sounds like a good idea. J/k. Or am I?

While the cocoa mixture cools, whisk together 2 cups each flour and sugar, with 1 teaspoon baking soda, and 1/2 teaspoon salt, then create a well in the center.

Now pour that wicked cocoa mixture into the center and whisk it all up. Ahhhh…


Finally, stir in 1/2 cup sour cream, which gives this cake a moistness that you will not find in any other cake. It. Is. So. Good.

Pour the cake batter into a non-stick sprayed baking sheet (I used a 12×17) or jelly roll pan, then bake at 350 degrees for 15 minutes. When’s the last time you baked a cake in 15 minutes?!

While the cake is baking, whisk together the Peanut Butter Icing, which was apparently so intoxicating that I forgot to take a picture of it!

Fear not, it’s just 3 cups powdered sugar, 3/4 cup peanut butter, 6 Tablespoons melted butter, 1/3 cup + 2 Tablespoons milk, and 1 teaspoon vanilla, whisked together in a bowl. Drizzle the icing down over the warm cake, then spread evenly and let it set before slicing.

If you can wait!!

Chocolate Sheet Cake with Peanut Butter Icing


Chocolate Sheet Cake with Peanut Butter Icing is my Aunt Mary’s recipe. So rich and decadent – make sure you’ve got some milk on hand!


  • For the Chocolate Sheet Cake:
    • 1 cup butter
    • 1 cup water
    • 1/4 cup cocoa powder
    • 2 cups flour
    • 2 cups sugar
    • 1 teaspoon baking soda
    • 1/2 teaspoon salt
    • 1/2 cup sour cream
  • For the Peanut Butter Icing:
    • 3 cups powdered sugar
    • 1/3 cup + 2 Tablespoons milk
    • 6 Tablespoons butter, melted
    • 1 teaspoon vanilla
    • 3/4 cup peanut butter


  1. Preheat oven to 350 degrees. Combine butter, water, and cocoa powder in a large saucepan then bring to a boil. Remove from heat then set aside to cool slightly.
  2. Whisk together flour, sugar, baking soda, and salt in a large bowl then create a well in the center. Add cocoa mixture then whisk until smooth. Add sour cream then whisk until smooth.
  3. Pour cake batter into a non-stick sprayed baking sheet (I used a 17x12) or jelly roll pan, then spread evenly. Bake for 15-18 minutes, or until a toothpick inserted into the center comes out clean.
  4. For the Peanut Butter Icing: Whisk together powdered sugar, milk, melted butter, and vanilla in a large bowl. Add peanut butter then whisk to combine. Microwave for 30 seconds then stir if too thick.  Pour over warm cake then spread evenly. Allow to cool then slice and serve.

This recipe is courtesy of Iowa Girl Eats,

This Chocolate Sheet Cake with Peanut Butter Icing is the BEST! Like I said – giant. peanut butter. cup. Plus it only takes 15 minutes to bake, and will be the hit of any party or get-together you take it to.

Just make sure you have some milk on hand!


Workout of the Day: 35 Minute, 3.7 Mile Treadmill Workout

Related Posts Plugin for WordPress, Blogger...


  1. This looks decadent!

  2. Kylee 11.06.2012

    This looks absolutely DIVINE!! Baking this today!!

  3. Lauren 11.06.2012

    Yay for voting! I grew up with a huge political influence from my dad and to this day, he still pressures me into voting no matter what election it is. He’s definitely right and I’m happy he does influence me in that way. I’m on my way to vote now! ;)

  4. Lindsey 11.06.2012

    Glad you voted! I vote “YES!” to this cake! :)

    • Lauren T 11.06.2012

      Haha. Yes the latest polls show this cake in the lead!

  5. Meagan 11.06.2012

    This looks amazing! I have been reading your blog for a while now and just wanted to let you know how much I appreciate all the “in process” pictures you take! I am still learning to cook/bake and having pictures of what things are supposed to look like as you go through the steps helps me so much! Not to mention, your recipes are delicious!

  6. Chocolate and peanut butter desserts are my favorite! My dad would love this sheet cake – yum!

  7. What a neat story about your grandma and the 19th amendment :) It’s especially important for you to get out and vote in Iowa! Here in California, a lot of my friends complain that their “vote doesn’t matter”…that is definitely not true in a swing state like yours!

    And can I just make a batch of that icing and put it on everything? Or would that just make me a freak? (don’t answer that)

  8. jennyv 11.06.2012

    I just have to say that I enjoyed the “J/K” — took me back :)

    Oh yes, and the sheet cake looks like something from a dreamland!

  9. Sylvia 11.06.2012

    I had to do a double cake after reading this cake recipe, no eggs?! I have a son with severe egg allergies so I am always on the lookout for eggless recipes. Yay!

    Unfortunately he is allergic to tree nuts, as well (I know, poor child). Any recommendations for an alternate frosting to go with this particular cake?

    Thanks for sharing!

    • Staci 11.06.2012


      Hope you don’t mind that I am jumping in this conversation. My family makes a cake JUST like this called “Texas Chocolate Sheet Cake” with a chocolate frosting/icing.
      Here it is:
      In a heavy pan bring the following to a low boil and stir constantly.
      6 tablespoons canned evaporated milk
      4 tablespoons cocoa

      1 pound butter (2 sticks)

      Remove pan from heat and add.
      1 box powdered sugar
 (4 cups) sifted.
      1 teaspoon vanilla
      1 cup of walnuts (optional)
      Stir until powdered sugar is dissolved.
      Pour on warm cake.

      Hope that helps!

      • Sylvia 11.06.2012


        YUM, that sounds delicious. That helps a lot, thanks! I will be making this for my little man (ok, and myself) very soon! :)

  10. Christine 11.06.2012

    I wish I lived in a swing state, I’d feel like my vote was worth something. Living in IL, my vote doesn’t hold much merit, even though “every vote counts”. Hope you chose the right candidate!

  11. Who doesnt love chocolate and peanut butter AND cake??? this looks like heaven on earth! :)

  12. Chris 11.06.2012

    Welcome to responsible citizenhood, Kristin. Always listen to your grandma.

    • heather 11.07.2012

      amen to this. (…and congrats on losing your voter V, kristin!! <3)

  13. If it tastes like a big Reese’s, I’m definitely in!!

  14. Amy M 11.06.2012

    I voted for the first time today too! Last time I was in China and didn’t bother with the absentee ballot. I did it for me and also so people don’t yell at me. :)

  15. Cherub Mamma 11.06.2012

    Yet another recipe that you post and I go make immediately.

    I don’t personally do anything with peanut butter. However, my family informs me that the cake is absolutely delicious! I love how quickly it came together. I love surprising everyone with dessert every now and then and this was a hit!!

  16. SWR 11.06.2012

    Yum! This looks great.

    You vote for the first time- I may have to bake my first sheet cake :)

  17. This almost looks too good to eat! ….who am I kidding, I could never say no to a chocolate and peanut butter combo!

    Congrats on voting for the first time! I have voted with an absentee ballot the past 2 presidential elections and am now starting to feel like I missed out on the true voting experience. Next time I might have to head out to the actual polls!

  18. M 11.06.2012

    Woo-hoo first time voter! And chocolate cake! Perfect pair!

    I really appreciate that you don’t get political on your blog…some blogs that I follow do and unfortunately it makes me hesitate a bit when I go to look at them. So thank you & keep it up!

  19. Liz 11.06.2012

    Shame on you for not voting before! My goodness, you have missed at least 2 elections! Glad you voted to uphold the rights we have:).

    I vote that the cake needs more icing!!

  20. Sheila 11.06.2012

    Ohhhh dear God….I think I just gained 5 lbs by looking at the pics of this amazeballllls dessert! Thx for sharing! Can’t wait to make it this weekend for my son when he comes home to visit from college! Chocolate/peanut butter are his favs!!

  21. Jeanine 11.06.2012

    Thanks for your blog. I am a Home Ec teacher and I use quite a few recipes in my classes and lots of other ones I use at home! I am always on the look out for recipes that can be completed in 39 minutes! Thats all we have for some grades. This Sheet cake will fit that. Thanks!

  22. Jess 11.07.2012

    Something about this cake reminds me of one from my own Midwestern roots! We’d always have chocolate sheet cakes with chocolate icing – so perfect for a crowd. But never did we have them with Peanut Butter Frosting – that’s definitely worth making a sheet cake this very weekend.

  23. Bek @ Crave 11.07.2012

    Woman after my own heart! That looks soooo good :)

  24. Trisha 11.07.2012

    This. Looks. Divine. And it’s making me reeeeally regret that I chose this week to get back on track with eating healthier. I’d love to devour this entire thing!
    Way to go on voting. I personally cannot imagine ever NOT voting. It’s such a fun right to have!

  25. Andrea 11.07.2012

    OMG!!! PB is my kryptonite and you just sent me over the edge with this! I’m going to request someone (hubs) makes me this for my birthday next Wednesday. Any more peanut butter recipes you want to throw out in the next week??? LOL.

  26. omg that is heavenly! I loveeeee peanut butter and chocolate! deliciousssss! (: PS: I’ll take leftovers!

  27. Like texas sheet cake, but better! I’m saving this recipe, it looks so easy to make!

  28. Oh my good gracious, this needs to be in my oven immediately!

  29. Trish 11.07.2012

    Yummy! Could you use greek yogurt instead of sour cream to up the protein content?? Pretending that it would be a healthy option to eat the whole thing for dinner :)

    • Iowa Girl Eats 11.08.2012

      Hahaha, I like where your head’s at. ;) I’m sure you could – let me know if you try, and what you think!

  30. Courtney F 11.07.2012

    Oh my starts that looks ah…may.zing!!!!

  31. Melissa in IA 11.07.2012

    I just love the lessons I’ve learned from my grandparents! For some reason, they really stay with me!! :)

    Now, about the cake…
    Chocolate and peanut butter together in one cake??? I’m in BIG trouble now!

  32. Kgrrrl 11.07.2012

    Wow, looks great and most things are already in my cupboard!!! Thanks for that! Also, good on ya for voting! I started when I was 18 (in Canada) and happy every time I line up and wait my turn. I hope you’re happy with the voting results, everyone in my country sure is!

  33. I’m so glad you voted. It was instilled in us to take advantage of that privilege and I have ever since I was able.

    The cake looks tremendous!

  34. OrGreenic 11.08.2012

    Thanks for the chocolate sheet cake recipe. The peanut butter icing looks delicious.

  35. Aunt Mary 11.08.2012

    You make me so proud! Love you!

  36. Amy S. 11.09.2012

    Made this last night and I almost had to hide it to keep my husband and daughter from eating the whole pan at once :) Thanks for sharing such a delicious recipe!!

    • Iowa Girl Eats 11.10.2012

      Teehee! Sounds like me – I had to take the leftovers over to my parent’s house because I could. not. stop! So glad you enjoyed it!

  37. Shelley 11.11.2012

    I made this cake this weekend during a trip to the NC mountains with friends for my birthday. It was possibly the best cake I’ve ever had, and I LOVE cake. I didn’t have a mixer to make the icing, so I used a store-bought buttercream and forced my brother whisk in the peanut butter. It was out of this WORLD! I sent the half that was left home to my parents with my bro, and I’m making a SECOND one tomorrow to take to the folks at work for my birthday. THANK YOU! It really is delicious and so easy!!! MAKE THIS CAKE, readers!

  38. Shari 11.11.2012

    We had dinner guests last night, and had a complete Iowa Girl Eats menu! We had your crock pot chicken tacos for dinner (though I just put all the fixings out and let everyone make their own), the Mexican rice you linked to when you posted the tacos, and finished with this FABULOUS cake. Everyone loved it! Then my husband, 5 year old and 8 year old all had more cake for breakfast. Peanut butter and dairy-that could be breakfast, right? Thank you so much for all of your wonderful posts!

    • Iowa Girl Eats 11.12.2012

      That is so great, and I’m SO glad you like the cake! Definitely breakfast worth! ;)

  39. This is warming as we speak. Smells amazing!!!

  40. emily 11.21.2012

    made this tonight for Thanksgiving! killing me that I can’t taste it yet!

  41. Sudha 12.26.2012

    I love this cake. I don’t have a sheet. Can I bake this in a regular 9 inch round pan?

  42. Sudha 12.27.2012

    I tried the cake yesterday. I made them as cup cakes. The top of the cake became very crusty and hard. I used exactly 1/2 the measurements. When I poured the cocoa into the flour/sugar mixture, the consistency was like a paste. Is that how it is supposed to be? I diluted it with additional water till I got a pourable consistency. Maybe, that was the problem, I used granulated sugar. Any ideas what I did wrong. The cup cake was too soft to hold its shape.

    • Iowa Girl Eats 01.01.2013

      Hi Sudha! Since I wasn’t there I can’t be positive what went wrong, I think adding water might have contributed to the problem, but the batter shouldn’t have been super thick to begin with.

  43. Andi 01.08.2013

    This sounds amazing!!! I think I will be making this asap! It sounds so easy to make! Am I missing something or are there no eggs in this recipe? Thanks!

  44. Debbi 01.19.2013

    I made this tonight for my brother’s bday and it was AMAZING! The cake was so moist and delicious and the frosting sooo decadent! And everyone else loved it too! My new favorite cake! Thank you!

  45. […] is chocolate cake, and this one goes one step further into the wonderland of indulgence. This Chocolate Sheet Cake with Peanut Butter Frosting is a must-try and is made with the simplest baking ingredients — you likely already have […]

  46. Jackie 02.09.2013

    I just made this for the second time tonight. The first time I made the cake I spaced and used my large sheet pan. I figure I’ll scrape out the cake and use it for some kind of trifle or something, the second one, now cooling, is for my sons 2nd bday party tomorrow night, it’s gonna be hard to wait until then.

    Also, love your blog and check your site, religiously, every day. Thanks for the great ideas and for what you do. The recipes are very accessible and have all turned out great!

  47. […] Cake from Annie’s Eats Crock Pot Chocolate Peanut Butter Cake from Chocolate and Carrots The Best Chocolate Sheet Cake with Peanut Butter Icing from Iowa Girl Eats Peanut Butter Cake from Shugary […]

  48. Domonique 05.19.2013

    This cake is delish!I made it this weekend for my mom’s bday and it was melt in your mouth delish. For those peanut butter fans they will shovel this in their mouths. Thanks for sharing!

  49. Mary 05.20.2013

    Just made the peanut butter frosting for a different cake, it is wonderful!!!! I had a half dozen ripe bananas to use up, so I had to make banana cake. I’ll try the chocolate sheet cake with this frosting soon!!!

  50. […] Chocolate Sheet Cake with Peanut Butter Icing: This recipe comes from my Aunt who has never baked anything I wouldn’t absolutely inhale. Great to have around for an easy treat on Memorial Day weekend. […]

Leave a Comment